This allows us to do something like

	config FB_RADEON
		select I2C_ALGOBIT if FB_RADEON_I2C

where FB_RADEON_I2C itself depends on FB_RADEON without getting a bogus
warning about recursive dependencies.

This matters because the select takes the default minimum dependancy
from the parent menu, so we want to do this under FB_RADEON rather than
under FB_RADEON_I2C (so that the I2C_ALGOBIT config depends properly
on the state of FB_RADEON)